Best cheap navigation device for footwell (not compass)

Just want it for pointing to the waypoint I am headed toward. BIG arrow or similar so visible at feet.
Don't need other metrics bc wearing a Garmin (can't see well at foot). And realize that simple direct route may not be desired route but just extra layer of safety when other things fail.

The crew i paddle with all put a garmin (various models) on the footstrap and can see the arrow perfectly well. Have you tried that? 

Zach